EXPERIMENTAL INFECTION WITH Toxocara cati IN PIGS: MIGRATORY PATTERN AND PATHOLOGICAL RESPONSE IN EARLY PHASE

Experimental inoculations of approximately 100,000 infective Toxocara cati larval eggs were done in twelve pigs. The T. cati eggs used for inoculation were collected from cat's feces. Another group of three pigs served as an uninfected control. Groups of infected pigs were euthanized at seven, 14, 21, and 28 days post-inoculation (dpi). Tissue samples were taken for digestion and histopathology changes in early phase. The number of larvae recovered from the lungs peaked at seven and 14 dpi and were also present at 21, and 28 dpi. Larvae of T. cati were present in the lymph nodes of the small and large intestine at seven, 14, and 28 dpi and at seven, 14, 21, and 28 dpi respectively. In other studied tissues, no larvae or less than one larva per gram was detected. The pathological response observed in the liver and lungs at seven and 14 dpi, showed white spots on the liver surface and areas of consolidation were observed in the lungs. The lungs showed an inflammatory reaction with larvae in center at 28 dpi. In the liver we observed periportal and perilobular hepatitis. The lymph nodes of the intestines displayed eosinophil lymphadenitis with reactive centers containing parasitic forms in some of them. The granulomatous reaction was not observed in any tissues. The role of the other examined tissues had less significance. The relevance of this parasite as an etiological agent that leads to disease in paratenic hosts is evident.

EFFECTS OF VITAMIN C SUPPLEMENTATION ON THE CHRONIC PHASE OF CHAGAS DISEASE

Introduction:In order to examine the effectiveness of vitamin C (ascorbic acid) in combating the oxidative insult caused by Trypanosoma cruzi during the development of the chronic phase of Chagas disease, Swiss mice were infected intraperitoneally with 5.0 × 104 trypomastigotes of T. cruzi QM1strain.Methods:Mice were given supplements of two different doses of vitamin C for 180 days. Levels of lipid oxidation (as indicated by thiobarbituric acid reactive substances-TBARS), total peroxide, vitamin C, and reduced glutathione were measured in the plasma, TBARS, total peroxide and vitamin C were measured in the myocardium and histopathologic analysis was undertaken in heart, colon and skeletal muscle.Results:Animals that received a dose equivalent to 500 mg of vitamin C daily showed increased production of ROS in plasma and myocardium and a greater degree of inflammation and necrosis in skeletal muscles than those that received a lower dose or no vitamin C whatsoever.Conclusion:Although some research has shown the antioxidant effect of vitamin C, the results showed that animals subject to a 500 mg dose of vitamin C showed greater tissue damage in the chronic phase of Chagas disease, probably due to the paradoxical actions of the substance, which in this pathology, will have acted as a pro-oxidant or pro-inflammatory.

Observações clínicas com um nôvo anti-helmíntico - triclorofenolpiperazina (CI-416) - no tratamento da ancilostomíase

O autor tratou 40 pacientes portadores de diversas helmintíases intestinais com um, nôvo sal de piperazina - Bis (2, 4, 5 - Triclorofenol) piperazina na dose única de 50 mg/kg de pêso corporal em jejum ou duas horas após a refeição matinal. Obteve com uma série de tratamento cura parasitológica em 25 pacientes (62,5%) infectados por Ancilostomídeos e mais 6 (15%) com um segundo curso da medicação, totalizando 31 pacientes curados parasitològicamente (77,5% dos casos). À tolerância ao produto foi boa, com exceção de dois casos (5%) que referiram vômitos logo após a ingestão da substância. Três enfermos relataram expulsão de exemplares adultos mortos de Ascaris lumbricoides pelas fezes. Com o esquema terapêutico empregado, o autor observou pequena atividade ãa droga com respeito à infecção por Ascaris lumbricoides e nula sôbre o Trichuris trichiura. Conclui que o nôvo antihelmíntico é bastante ativo contra a infestação determinada pelos Ancilostomídeos.

Avaliação sorológica de vacinação anti-rubéola em dois educandários no Estado da Guanabara

196 soros de crianças provenientes de dois educandários da Guanabara foram ensaiados quanto à presença de anticorpos para rubéola. através do teste de inibição de hemaglutinação. Apenas 24 crianças sem anticorpos foram encontradas e destas crianças susceptíveis um grupo foi vacinado com amostra Cendehill liofilizada do Lab. R.I.T. (Genval, Bélgica), sendo o outro grupo deixado como controle. Observou-se 100% de formação de anticorpos para rubéola no grupo vacinado. O alto nivel de anticorpos pré-vacinais encontrado sugere alta circulação do vírus cla rubéola em nosso meio.

Scanning electron microscopy and X-ray spectroscopy applied to mycelial phase of sporothrix schenckii

Scanning electron microscopy applied to the mycelial phase of Sporothrix schenckii shows a matted mycelium with conidia of a regular pattern. X-Ray microanalysis applied in energy dispersive spectroscopy and also in wavelength dispersive spectroscopy reveals the presence of several elements of Mendeleef's classification.

Estudo da resposta imunitária à vacinação anti-meningocócica com polissacarídeos de diversas procedências

Um estudo duplamente cego sobre a capacidade de indução de anticorpos séricos anti-meningocócicos por polissacarfdeos capsulares A e C, detectados pela técnica de hemaglutinação passiva, foi realizado no período de outubro a dezembro de 1974. Analisaram-se as respostas imunogênicas de polissacarídeos isolados e combinados de três procedências, entre as quais a de um laboratório que se propunha a produzi-los em larga escala e que já os havia testado em um grupo de voluntários sem reações colaterais importantes. Duzentos e trinta e oito voluntários, funcionários e internos de uma penitenciária, foram divididos em 6 grupos aos quais foram administrados toxóide tetânico e cinco diferentes tipos de vacina. Colheitas de sangue imediatamente antes e quatro semanas após a inoculação foram realizadas e a conversão soro lógica analisada. As vacinas polissacarídeas C mostraram boa resposta imunogênica, enquanto a vacina A mostrou resposta mais pobre. As vacinas em experimentação que continham polissacarídeo A não demonstraram poder antigênico, apresentando, inclusive, resposta paradoxal, com a formação de anticorpos anti-meningocócicos C. Reações colaterais nos grupos submetidos a estas vacinas, embora de pequena intensidade, mostraram-se mais freqüentes do. que nos outros grupos, sugerindo, como depois se evidenciariam, problemas de purificação. A inoculação de vacinas mono vai entes determinou uma queda de níveis de anticorpos não específicos (queda de anti-polissacarfdeo A quando a vacina era polissacarfdea C e vice-versa), sugerindo, juntamente com achados de outros estudos, um possível mecanismo de depressão imunitária que merece ser melhor investigado.

Studies on anti-component 5 antibodies in animals infected with Trypanosoma cruzi

A competitive antibody enzyme immunoassay, using a monoclonal antibody against the species-specific Trypanosoma crnzi antigen 5, was used to investigate the presence of anti-component 5 antibodies in sera of opossums, dogs, rabbits and rats infected with this parasite. The sera from 51 Venezuelan patients with Chagas’disease were also tested. About 90% of the infected subjects showed significant levels of anti-component 5 antibodies. Nevertheless, these antibodies were not detected in the sera of dogs, rats and opossums infected with T. cruzl Some sera from infected rabbits presented significant results but close to the limit ofpositivity ofthe test. These findings suggest that the immune response in animals naturally or experimentally infected with T. cruzi is different from that observed in human Chagas’disease.

Freqüência de indivíduos com anticorpos sericos anti-Cysticercus cellulosae em cinco Municípios do Estado de São Paulo

Considerando a importância da cisticercose humana em Saúde Pública, foi estudada a freqüência de positividade da detecção de anticorpos anti-Cysticercus cellulosae em 1.264 amostras de soro, assim distribuídas: Grupol-1.064 de indivíduos da população geral (821 adultos e 243 crianças) residentes em cinco municípios do Estado de São Paulo (São Paulo, Presidente Prudente, Santos, Campinas e Marília), Brasil; Grupo 11-200 de pacientes adultos internados em hospital psiquiátrico (Presidente Prudente). Para a pesquisa dos anticorpos séricos foi empregado o teste ELISA utilizando como suporte discos de tecido-resina. No Grupo I foram encontrados 18 (2,30%) soros reagentes entre as amostras de adultos, e 2 (0,82%) entre as das crianças; entre os doentes psiquiátricos, Grupo II, a freqüência de positividade foi de 5 %, significativamente maior (p < 0.05).

Leptospirose em doentes com anticorpos anti-HIV: relato de dois casos

Relata-se a concomitância de leptospirose e síndrome da imunodeficiência adquirida (SIDA) em humanos. Nestes casos não foram observados aspectos clínicos diferentes que possam ser atribuídos à simultaneidade dessas patologias.

Incidence of anti-toxoplasma antibodies in women with high-risk pregnancy and habitual abortions

Toxoplasmosis is a zoonosis caused by Toxoplasma gondii, an obligate intracellular parasite. In pregnant women on the worldwide scale, there are seroprevalences from 7% to 51.3% and in women with abnormal pregnancies and abortions the seroprevalences vary from 17.5% to 52.3%. In Mexico, seropositivity has been found to vary from 18.2% to 44.8% in women with abnormal deliveries or abortions. This study's aim was to determine the incidence oflgG and IgM anti-Toxoplasma antibodies in women at the Gineco-Obstetrics Hospital of the Western Medical Center of the Mexican Social Security Institute. Three hundred and fifty women with high-risk pregnancies were studied, and 122 (34.9%) were found to be IgG seropositive and 76 (20.7%) were IgM positive. In one group of women with habitual abortions there were 48 (44.9%) with the preseiwe of IgG antibodies and 33 (33-3%) were IgM seropositive. Seropositivity was analyzed according to age, occupation, socio-economic level, eating raw or poorly cooked meat, and living with cats.

Prevalence of IgG and IgM anti-Toxoplasma antibodies in patients with HIV and acquired immunodeficiency syndrome (AIDS)

With the emergence of the human immunodeficiency virus (HIV), in patients with acquired immunodeficiency syndrome (AIDS), Toxoplasma gondii has arisen as an important opportunist pathogenic agent, especcially in the central nervous system, being the most common cause of intracerebral lesions. The incidence of Toxoplasma gondii in HIV-infected patients depends principally on the existence of latent Toxoplasma parasitosis in the population affected. Through the enzyme-linked immunosorbent assay (ELISA), IgG and IgM anti-Toxoplasma antibodies were found in 92 patients of which 46 (50.0%) were IgG seropositive, and only one case (1.0%) had IgM antibodies.Of the 92 patients: 53 were HIV seropositives and 39 had AIDS. The detection and monitoring of anti-Toxoplasma antibodies in HIV patients is essential, since in this group there is a high percentage risk of developing cerebral toxoplasmosis, which is the second cause of death in this type of patients.